Weaning starts at about 2-3 weeks old, although they are able to digest solid food from day 1, and should be given plenty of alfalfa pellets and veg such as lettuce/bell peppers/parsley. Make sure to separate any boys at 21 days to avoid dangerousinbreeding/backbreeding.

Guinea pigs wean at anywhere from two to three weeks of age (you should also separate any boys at three weeks to avoid future pregnancies which can be very dangerous especially if mum gets pregnant again so soon after her current litter, and there are also inbreeding risks). However they will also eat solid foods immediately after birth.

Baby guinea pigs should start eating solid food (hay, veggies, even pellets) the day they are born, although they will continue to nurse as well. Weaning may occur at two or three weeks: eventually mama pig will start shoving them away. Separate any boys at three weeks (21 days) to avoid backbreeding.

This happens after a fortnight or so, but they will eat solid food (pellets, veg, hay) from birth also. Make sure to give them alfalfa pellets (like Oxbow Cavy Performance) until about 6 months of age. Separate any boys after 21 days to avoid dangerous inbreeding/backbreeding.